This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the presently described embodiments. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present embodiments. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
Oil and gas wells frequently require subsurface maintenance and remediation to maintain adequate flow or production. Intervention operations on subsea wells require specialized intervention equipment to pass through the water column and to gain access to the well. The system of valves on the wellhead is commonly referred to as the “tree” and the intervention equipment is attached to the tree with a well access or well intervention package. For example, a well access package may be used for a variety of services, including pumping fluids, such as chemicals, into the well, maintaining and testing the wellhead or the tree, performing slickline type operations, in addition to other types of services and operations.
Accordingly, well intervention may enable various treatment chemicals to be injected into the well, such as to reduce the build-up of substances in production flowlines as the product flows from the well to a topside production facility (e.g. corrosion inhibitors, scale inhibitors, paraffin inhibitors, hydrate inhibitors, and demulsifiers), and also enable operations related to well stimulation, well kill, flow assurance, scale management, in addition to others.
A known method for well intervention involves the use of a remotely operated vehicle (ROV) and a subsea skid. Current state of the art methods require that the well access package and skid be assembled on the surface and then lowered to the seafloor with winches. When the well access package is in the vicinity of the tree, the ROV is used to guide the skid into position and locked to the tree. A control umbilical attached to the skid is then used to operate the various functions required to access the well. The umbilical provides control functions for the well access package and skid, as well as a conduit for various fluids, included chemical treatment fluids, circulated in or through the skid.
Existing skids typically have a direct hydraulic control or multiplexer (MUX) control system to operate valves on the skid. This requires there to be an electrical cable or hydraulic hose from the vessel at surface to the skid subsea. However, with subsea operations only moving to deeper waters and more remote locations, it remains a priority to maintain or increase the functionality of subsea skids and similar equipment while minimizing the burden of support and maintenance for such equipment.